Volcanism and continental break-up: a global compilation of large igneous provinces

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Abstract Large igneous provinces (LIPs) include continental flood basalts and associated intrusive rocks, volcanic passive margins, oceanic plateaus, submarine ridges, seamount groups, and ocean basin flood basalts. In some cases transient episodes of voluminous magmatism are temporally and spatially related to continental break-up, e.g. North Atlantic Volcanic Province, Deccan Traps, Paraná-Etendeka basalts. In other cases, however, no relationships are apparent, e.g. Siberian flood basalts, Columbia River flood basalts. Herein we review LIPs worldwide in order to better understand their relationship to the break-up and separation of lithospheric plates. The two most voluminous episodes known of basaltic magmatism not associated with the creation of ‘normal’ oceanic crust, the emplacements of the Ontong Java and Kerguelen plateaus, do not appear to be linked to continental break-up. Volcanic passive margins have now been identified on the edges of many continents, and are clearly related to continental break-up and separation. They cannot always, however, be tied to continental flood basalts. Ocean basin flood basalts and seamount groups are not commonly related to continental break-up. In most instances submarine ridges show temporal and spatial relationships with continental flood basalt provinces or oceanic plateaus. Observational data suggest that existing models do not adequately explain all LIPs; we suggest that a thermally and chemically heterogeneous asthenosphere, occasionally penetrated by deep mantle plumes, can account for their origin.